diff options
Diffstat (limited to 'lib/dns/soa.c')
| -rw-r--r-- | lib/dns/soa.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/lib/dns/soa.c b/lib/dns/soa.c new file mode 100644 index 0000000..83a1c17 --- /dev/null +++ b/lib/dns/soa.c @@ -0,0 +1,111 @@ +/* + * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 2000, 2001 Internet Software Consortium. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH + * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, + * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + * PERFORMANCE OF THIS SOFTWARE. + */ + +/* $Id: soa.c,v 1.8 2007/06/19 23:47:16 tbox Exp $ */ + +/*! \file */ + +#include <config.h> + +#include <isc/util.h> + +#include <dns/rdata.h> +#include <dns/soa.h> + +static inline isc_uint32_t +decode_uint32(unsigned char *p) { + return ((p[0] << 24) + + (p[1] << 16) + + (p[2] << 8) + + (p[3] << 0)); +} + +static inline void +encode_uint32(isc_uint32_t val, unsigned char *p) { + p[0] = (isc_uint8_t)(val >> 24); + p[1] = (isc_uint8_t)(val >> 16); + p[2] = (isc_uint8_t)(val >> 8); + p[3] = (isc_uint8_t)(val >> 0); +} + +static isc_uint32_t +soa_get(dns_rdata_t *rdata, int offset) { + INSIST(rdata->type == dns_rdatatype_soa); + /* + * Locate the field within the SOA RDATA based + * on its position relative to the end of the data. + * + * This is a bit of a kludge, but the alternative approach of + * using dns_rdata_tostruct() and dns_rdata_fromstruct() would + * involve a lot of unnecessary work (like building domain + * names and allocating temporary memory) when all we really + * want to do is to get 32 bits of fixed-sized data. + */ + INSIST(rdata->length >= 20); + INSIST(offset >= 0 && offset <= 16); + return (decode_uint32(rdata->data + rdata->length - 20 + offset)); +} + +isc_uint32_t +dns_soa_getserial(dns_rdata_t *rdata) { + return soa_get(rdata, 0); +} +isc_uint32_t +dns_soa_getrefresh(dns_rdata_t *rdata) { + return soa_get(rdata, 4); +} +isc_uint32_t +dns_soa_getretry(dns_rdata_t *rdata) { + return soa_get(rdata, 8); +} +isc_uint32_t +dns_soa_getexpire(dns_rdata_t *rdata) { + return soa_get(rdata, 12); +} +isc_uint32_t +dns_soa_getminimum(dns_rdata_t *rdata) { + return soa_get(rdata, 16); +} + +static void +soa_set(dns_rdata_t *rdata, isc_uint32_t val, int offset) { + INSIST(rdata->type == dns_rdatatype_soa); + INSIST(rdata->length >= 20); + INSIST(offset >= 0 && offset <= 16); + encode_uint32(val, rdata->data + rdata->length - 20 + offset); +} + +void +dns_soa_setserial(isc_uint32_t val, dns_rdata_t *rdata) { + soa_set(rdata, val, 0); +} +void +dns_soa_setrefresh(isc_uint32_t val, dns_rdata_t *rdata) { + soa_set(rdata, val, 4); +} +void +dns_soa_setretry(isc_uint32_t val, dns_rdata_t *rdata) { + soa_set(rdata, val, 8); +} +void +dns_soa_setexpire(isc_uint32_t val, dns_rdata_t *rdata) { + soa_set(rdata, val, 12); +} +void +dns_soa_setminimum(isc_uint32_t val, dns_rdata_t *rdata) { + soa_set(rdata, val, 16); +} |